Fitting assembly for internally sealing a corrugated tube and a method for using the same

ABSTRACT

A fitting assembly for corrugated tubing is provided including a body, an insert, locking means and a bushing. The body includes first connecting means. The locking means includes second connecting means. The insert is sealingly engaged with the body and includes a transition area of increased outside diameter. The bushing includes an inwardly projecting protrusion for engagement with a trough disposed on an external surface of a corrugated tube. The first and second connecting means engage to removably secure the bushing, an end of the corrugated tube and at least a portion of the insert within the body and the locking means to pinch a circumferential section of the corrugated tube between the protrusion and the transition area, and to seal an internal surface of the circumferential section with the transition area.

This application claims priority from provisional application serial No.60/701,072, filed Jul. 19, 2005, the disclosure of which is incorporatedby reference in its entirety.

FIELD OF THE INVENTION

This present invention is generally directed to a fitting assembly forsealing a corrugated tube and more specifically directed to sealing aportion of the fitting assembly with an internal section of thecorrugated tube.

BACKGROUND OF THE INVENTION

In plumbing applications, sections of pipe, tubing, or conduit aretypically connected to one another to provide for the flow of fluidswithin a system. In connecting these sections, it is generally desirableto seal the connections in order to avoid or at least minimize the lossof fluid due to leaks or fugitive emissions. Various techniques existfor sealing the connections. Two of such techniques include welding andthe use of adhesives.

When sections of pipe, tubing, or conduit are connected by welding,disconnection for service, repair, routine maintenance, or restructuringof the system often involves cutting or otherwise physically separatingthe sections. Disconnection usually involves cutting using high speedrotary tools. When the sections being cut apart are metal, sparks areoften generated, which creates an undesirable condition. Even if thesections being cut are plastic, dust or flying debris may be generated.In either case, the integrity of the pipe, tubing, or conduit iscompromised, and new sections must be fabricated and reinstalled.

When sections are connected with adhesives, disconnection may alsoinvolve cutting or some other physical method of separation (e.g.,melting the adhesive), or it may involve effecting a chemical change tothe adhesive. Melting the adhesive or using chemical techniques toseparate the sections are often time consuming and costly practices.Reassembly of the system generally involves adhesively connecting newsystems of pipe.

Therefore, connectors and fittings which provide releasable sealingcapability are preferred for applications where disassembly is likely.Various connectors and fittings having releasable sealing capability areused to seal the outside surfaces of sections of pipe, tubing, orconduit with one another. However, in applications using corrugatedtubing, inside and outside surfaces have ridges and troughs makingsealing with prior art connectors and fittings ineffective. In addition,sealing on the outside surface of tubing is undesirable because walls ofthe tubing can become unintentionally distorted when the connector issecured thereby increasing the potential for leakage.

There is a need to provide a fitting or connector for releasably sealingcorrugated tubing where the sealing is made inside the tubing. Prior artconnectors and fittings for addressing these needs were either tooexpensive, inefficient, ineffective, or a combination of all of these.Based on the foregoing, it is the general object of the presentinvention to improve upon or overcome the problems and drawbacks of theprior art.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, a fitting assembly fora corrugated tube includes a body, an insert, a locking device, and abushing. The body includes a first connector, a first bore, a firstshoulder, and a second shoulder. The insert is receivable on the secondshoulder and has a second bore, two external surfaces (one of increasedoutside diameter), and a transition area between the two externalsurfaces. The locking device has a second connector that is selectivelyreceivable on the first connector. The bushing is slidable over theinsert and securable in the body and the locking device via the firstand second connectors.

According to another aspect of the present invention, an internallysealable fitting assembly includes a body having a bore; an insertcoaxially positioned in the bore; a castellated bushing receivable oversaid insert; and a locking device selectively receivable on the body.The insert is dimensioned to receive a corrugated tube thereon.Receiving the locking device on the body urges the bushing against thecorrugated tube to clamp the corrugated tube against the insert.

When the fitting is assembled, the first and second connectors engage toreleasably secure the bushing, the end of the corrugated tube, and atleast a portion of the insert within the body and the locking device. Inaddition, a circumferential section of the corrugated tube is clampedbetween the protrusion and the transition area to seal an internalsurface of the circumferential section with the transition area.

In another aspect of the present invention, a method of installing afitting assembly for a corrugated tube includes providing the fittingassembly, sliding a locking device of the fitting assembly onto thecorrugated tube, sliding a bushing of the fitting assembly onto thecorrugated tube, positioning a protrusion on the bushing into a troughin the corrugated tube, abutting an insert against a surface in a bodyto sealingly engage the insert with the body, sliding the lockingdevice, the bushing, and the corrugated tube over the insert, andengaging the locking device and the body to releasably secure thebushing, an end of the corrugated tube, and at least a portion of theinsert within the body and the locking device. When the locking deviceand the body are fully engaged, a circumferential section of thecorrugated tube is clamped between the protrusion and the insert to sealthe corrugated tube.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded cross sectional view of the fitting assembly for acorrugated tube.

FIG. 2 is a cross sectional view of the fitting assembly installed on asection of corrugated tube.

FIG. 3 is a view of detail A of FIG. 2 illustrating a circumferentialsection of the corrugated tube held between the projection and thetransition area.

FIG. 4 is a top view of an embodiment of a castellated bushing.

FIG. 5 is a cross sectional view of the castellated bushing shown inFIG. 4.

FIG. 6 is a cross sectional view of an embodiment of the body having theinsert integral therewith.

FIG. 7 is a cross sectional view of locking means having the bushingintegral therewith.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, a fitting assembly for sealing an end of acorrugated tube to create a gas or liquid seal is shown at 10. Thefitting assembly 10 includes a body 12, an insert 14, a locking device16, and a bushing 18 and can be used between lengths of corrugated tube,as an adapter to another coupling device or fitting, or to terminate alength of corrugated tube. Sealing is effected between an inner surfaceof the corrugated tube and an outer surface of the insert 14 received inan end of the corrugated tube.

The body 12 includes a first connector 20 having male threads, a firstbore 22, a first shoulder 24, and a second shoulder 26. The first bore22 transitions to a reduced cross section 28 at the first shoulder 24,and the reduced cross section transitions to a further reduced crosssection 30 at the second shoulder 26. While the first connector 20 isshown as having male threads, the present invention is not limited inthis regard as other connecting means may also be utilized including butnot limited to bayonet type connections. The body 12 may also have malethreads 25 located on an end opposite the end at which the firstconnector 20 is shown to facilitate the connection to any other devicehaving connectable female threads. In the alternative, the body 12 maybe capped at the end opposite the end at which the first connector 20 isshown.

The insert 14, which provides for the free flow of fluid (or at leastnegligible or minimal restriction of fluid flow), has a second bore 23and a transition area 32. The transition area 32 is defined by a curvedsurface that extends radially from a portion of the external surface ofthe insert to another portion of the external surface having anincreased outside diameter. The insert 14 is coaxially received in thebore 22, and at least a portion of one end 34 of the insert 14 abuts thesecond shoulder 26 to sealingly engage the insert with the secondshoulder. While the insert 14 is described as being sealing engaged withthe second shoulder 26, the present invention is not limited in thisregard as the insert may be sealingly engaged with the reduced crosssection 28, any suitable surface of the body 12, or a combinationthereof.

The bushing 18 is a castellated member defined by a plurality of splitsformed, cut, or otherwise disposed at a first end 40. An inwardlyprojecting protrusion 42 is located at the first end 40. The inwardlyprojecting protrusion 42 is configured such that as the bushing 18 isreceived over corrugated tubing, the splits allow the bushing to flex sothat the surfaces of the inwardly projecting protrusion are received onthe external surfaces of the corrugation.

The locking device 16 is a member having a through bore 39 extendingtherethrough. A second connector 36 defined by female threads is locatedin the through bore. 39 proximate one end in which the bushing 18 isreceived. The opposing end includes a receiving shoulder 38 on which thebushing may be received. The locking device 16 is open at the end havingthe second connector 36 to receive the bushing 18, the insert 14, andthe body 12 and is also open at the opposite end to allow the corrugatedtube to extend therethrough. While the second connector 36 is describedas having female threads, the present invention is not limited in thisregard as other connectors may also be utilized including, but notlimited to, bayonet-type connections.

Referring to FIG. 2, the first connector 20 on the body 12 and thesecond connector 36 on the locking device 16 engage to releasably securethe body and the locking device together. An opposing end 50 of thebushing 18 is seated on the receiving shoulder 38 of the locking device16. Securing the body 12 and the locking device 16 together urges thebushing and an end 47 of the corrugated tube 48 over the insert 14towards the first shoulder 24. The first connector 20 and the secondconnector 36 engage to seal the corrugated tube 48 to the insert 14 andto secure the bushing 18, the end 47 of the corrugated tube, and atleast a portion of the insert within the body 12 and the locking device16.

Referring now to FIG. 3, when the fitting assembly 10 is properlyassembled with a corrugated tube 48, the protrusion 42 on the bushing 18engages with a trough 44 in or formed by an external surface 46 of thecorrugated tube. When the protrusion 42 engages the trough 44, acircumferential section 52 of the corrugated tube 48 is clamped betweenthe protrusion and the transition area 32, thereby sealing an internalsurface 54 of the circumferential section with the transition area. Thesealing engagement between the internal surface 54 and the transitionarea 32 is maintained until the body 12 is released relative to thelocking device 16, which causes the bushing 18 and the insert 14 to movein opposite directions, thereby releasing the internal surface from thetransition area.

Referring now to FIGS. 4 and 5, the bushing 18 is shown as having foursplits 56 extending through the protrusion 42, the splits terminatingbetween the first end 40 and the opposing end 50. The splits 56 arecircumferentially disposed around the bushing 18 for allowing thebushing to flex when sliding the bushing axially along the corrugatedtube 48 shown in FIGS. 2 and 3. While four splits 56 are illustrated,the present invention is not limited in this regard as the bushing mayhave any number of cuts to allow the bushing to flex.

Referring now to FIG. 6, a body 212 is shown having an integral insert214. The insert 214 is attached to the body 212 at a first shoulder 224.A transition area 232 is formed on the exterior surface of the insert214. A connector 220 having male threads is formed on the body 212 toallow the body to be connected to a locking device.

Referring now to FIG. 7, a locking device 316 is shown having anintegral bushing 318. The bushing 316 is shown having splits 356 forallowing the bushing to flex when the bushing is pushed axially alongthe corrugated tube 48 shown in FIGS. 2 and 3.

Referring generally to FIGS. 1-6 the insert 14, 214 is manufactured froma material softer than the corrugated tube 48. Similarly, the body 12,212 is manufactured from a material softer than the corrugated tube 48.While the insert 14, 214 is said to be softer than the corrugated tube48, the present invention is not limited in this regard as in anotherembodiment of the present invention the insert may be manufactured froma material which is as hard as or harder than the corrugated tube.Although the body 12, 212 is said to be softer than the corrugated tube48, the present invention is not limited in this regard as in anotherembodiment the body may be manufactured from a material which is as hardas or harder than the corrugated tube.

A method of using the fitting assembly for the corrugated tube 48 asshown in FIGS. 1-5 includes the steps of providing the fitting assembly10; sliding the locking device 16 onto the corrugated tube 48; slidingthe bushing 18 onto the corrugated tube; positioning the protrusion 42into the trough 44; abutting the insert 14 against the second shoulder26 to sealingly engage the insert with the body 12; sliding the lockingdevice, the bushing, and the corrugated tube over the insert towards thefirst shoulder; and engaging the first and second connectors toremovably secure the bushing, an end 47 of the corrugated tube, and atleast a portion of the insert within the body by clamping acircumferential section 52 of the corrugated tube between the transitionarea and the protrusion, thereby sealing an internal surface 54 of thecircumferential section with the transition area.

Another method of using the fitting assembly for the corrugated tube asshown in FIG. 6 includes the steps of providing a fitting assembly inwhich the body 212 is integral with the insert 214; sliding the lockingdevice onto the corrugated tube; sliding the bushing onto the corrugatedtube; positioning the protrusion in the trough of the corrugated tube;sliding the locking device, the bushing, and the corrugated tube overthe insert 214; and engaging the first and second connectors toreleasably secure the bushing and an end of the corrugated tube withinthe body by clamping the corrugated tube and sealing an internal surfaceof the corrugated tube against insert.

Another method of using the fitting assembly for a corrugated tube asshown in FIG. 7 includes the steps of providing a fitting assembly inwhich the bushing 318 is integral with the locking device 316; slidingthe integral bushing and locking device onto the corrugated tube;positioning the protrusion 342 of the bushing in the trough of thecorrugated tube; sliding the corrugated tube over the insert; andengaging first and second connectors on the body and locking device,respectively, to releasably secure the bushing, an end of the corrugatedtube, and at least a portion of the insert within the body by clampingthe corrugated tube and sealing an internal surface of the corrugatedtube against insert.

Although the present invention has been disclosed and described withreference to certain embodiments thereof, it should be noted that othervariations and modifications may be made, and it is intended that thefollowing claims cover the variations and modifications within the scopeof the invention.

1. A fitting assembly for a corrugated tube comprising: a body having first connecting means, a first bore, a first shoulder in said first bore, and a second shoulder in said first bore; an insert having a second bore, a first external surface, a second external surface of increased outside diameter, and a transition area intermediate said first external surface and said second external surface, said insert being receivable in said first bore; locking means having a through bore, a receiving shoulder in said through bore, and second connecting means selectively receivable on said first connecting means; and a bushing slidable over said insert and securable in said body and said locking means, a first end of said bushing having an inwardly projecting protrusion for engagement with a trough disposed on an external surface of a corrugated tube.
 2. The fitting assembly of claim 1, wherein said first bore transitions to a reduced cross section at said first shoulder and wherein said reduced cross section transitions to a further reduced cross section at said second shoulder.
 3. The fitting assembly of claim 1, wherein at least a portion of one end of said insert abuts at least a portion of said second shoulder, and wherein said insert is sealingly engaged with said body.
 4. The fitting assembly of claim 1, wherein a second end of said bushing seats on said receiving shoulder for urging said bushing and an end of said corrugated tube over said insert towards said body.
 5. The fitting assembly of claim 1, wherein said first connecting means and said second connecting means engage to releasably secure said bushing, said end of said corrugated tube, and at least a portion of said insert within said body and said locking means.
 6. The fitting assembly of claim 5, wherein the engagement of said first connecting means and said second connecting means clamps a circumferential section of said corrugated tube between said protrusion and said transition area to seal an internal surface of said circumferential section with said transition area.
 7. The fitting assembly of claim 1 wherein said bushing has a plurality of splits axially extending though said protrusion, said splits terminating between said first end and a second end of said bushing, wherein said splits are circumferentially disposed around said bushing to allow said bushing to flex when sliding said bushing along said corrugated tube.
 8. The fitting assembly of claim 1 wherein said insert is integral with said body.
 9. The fitting assembly of claim 1, wherein said bushing is integral with said locking means.
 10. The fitting assembly of claim 1 wherein said insert is made from a material that is harder than said corrugated tube.
 11. The fitting assembly of claim 1 wherein said insert is made from a material that is softer than said corrugated tube.
 12. The fitting assembly of claim 1 wherein said body is made from a material that is harder than said corrugated tube.
 13. The fitting assembly of claim 1 wherein said body is made from a material that is softer than said corrugated tube.
 14. The fitting assembly of claim 1 wherein said first connecting means comprises male threads and wherein said second connecting means comprises female threads.
 15. An internally sealable fitting assembly, comprising: a body having a bore; an insert coaxially positioned in said bore, said insert being dimensioned to receive a corrugated tube thereon; a castellated bushing receivable over said insert and said corrugated tube; and a locking device selectively receivable on said body; wherein receiving said locking device on said body urges said bushing against said corrugated tube to clamp said corrugated tube against said insert.
 16. The internally sealable fitting assembly of claim 15, wherein said bushing comprises a protrusion disposed at the castellated end.
 17. The internally sealable fitting assembly of claim 16, wherein said protrusion is receivable in a trough of said corrugated tube to clamp said corrugated tube against said insert.
 18. The internally sealable fitting assembly of claim 15, wherein said insert is integral with said body.
 19. The internally sealable fitting assembly of claim 15, wherein said bushing is integral with said locking device.
 20. The internally sealable fitting assembly of claim 15, wherein said insert comprises a radially-extending curved surface against which said corrugated tube can be clamped.
 21. A method of installing a fitting assembly for a corrugated tube, said method comprising the steps of: providing a fitting assembly for said corrugated tube comprising a body having first connecting means, a first bore, a first shoulder, and a second shoulder; wherein said first bore transitions to a reduced cross section at said first shoulder, and wherein said reduced cross section transitions to a further reduced cross section at said second shoulder; an insert having a second bore and a transition area of increased outside diameter; locking means having second connecting means disposed therein and an internally directed receiving shoulder; a bushing, a first end thereof having an inwardly projecting protrusion for engagement with a trough disposed on an external surface of said corrugated tube; wherein an opposing end of said bushing seats on said receiving shoulder; sliding said locking means onto said corrugated tube, sliding said bushing onto said corrugated tube, positioning said protrusion into said trough, abutting said insert against said second shoulder to sealingly engage said insert with said body, sliding said locking means, said bushing, and said corrugated tube over said insert towards said first shoulder; and engaging said first and second connecting means to removably secure said bushing, an end of said corrugated tube, and at least a portion of said insert within said body and said locking means, to clamp a circumferential section of said corrugated tube between said transition area and said protrusion and to seal an internal surface of said circumferential section with said transition area. 